Bidirectional Uplink/Downlink Handoff

1. A method for selecting coverage areas as candidates for a bidirectional handoff, the method comprising: a mobile station engaging in a communication session via an access network, wherein an uplink connection is provided for uplink traffic in the communication session and a downlink connection is provided for downlink traffic in the communication session; the mobile station receiving a list of coverage areas that are general candidates for a bi-directional handoff, wherein the list of general handoff candidates is received from the access network; the mobile station determining an uplink-resource demand and a downlink-resource demand of the mobile station, for the communication session; the mobile station using the uplink-resource demand as a basis for selecting one or more coverage areas from the list of general handoff candidates as candidates for an uplink handoff of the uplink connection; and the mobile station using the downlink-resource demand as a basis for selecting one or more coverage areas from the list of general handoff candidates as candidates for a downlink handoff of the downlink connection; and the mobile station sending a message to the access network that identifies the one or more candidates for the uplink handoff and the one or more candidates for the downlink handoff.

2. The method of claim 1 , wherein the communication session is of a given type, wherein determining the uplink-resource demand of the mobile station for the communication session comprises determining a general level of uplink-resource demand for the type of the communication session; and wherein determining the downlink-resource demand of the mobile station for the communication session comprises determining a general level of downlink-resource demand for the type of the communication session.

3. The method of claim 1 , wherein determining the uplink-resource demand and the downlink-resource demand of the mobile station for the communication session comprises: measuring usage of uplink resources and usage of downlink resources by the mobile station over a given period of time during the communication session; based, at least in part, on the usage of uplink resources, determining the uplink-resource demand of the mobile station for the communication session; and based, at least in part, on the usage of downlink resources, determining the downlink-resource demand of the mobile station for the communication session.

4. The method of claim 1 , wherein the uplink connection is initially provided in a source coverage area of the access network, the method further comprising: the mobile station receiving a message that indicates an uplink-target coverage area from the candidates for the uplink handoff; and the mobile station performing the uplink handoff from the source coverage area to the uplink-target coverage area.

5. The method of claim 1 , further comprising the mobile station receiving a response message from the access network that identifies a first target coverage area for the uplink handoff and a second target coverage area for the downlink handoff, wherein the response message is sent as a response to the message that identifies the one or more candidates for the uplink handoff and the one or more candidates for the downlink handoff.

6. The method of claim 1 , wherein the downlink connection is initially provided via a source coverage area, the method further comprising: the mobile station receiving a message that indicates a downlink-target coverage area from the candidates for the downlink handoff; and the mobile station performing the downlink handoff from the source coverage area to the downlink-target coverage area.

7. The method of claim 1 : wherein selecting the one or more candidates for the uplink handoff from the received list of general handoff candidates comprises, for each coverage area in the received list of general handoff candidates: determining available uplink resources in the coverage area; and making a determination as to whether or not the available uplink resources in the coverage area are sufficient to meet the uplink-resource demand and if the determination is that the available uplink resources in the coverage area are sufficient, selecting the coverage area as a candidate for the uplink handoff; and wherein selecting the one or more candidates for the downlink handoff from the received list of general handoff candidates comprises, for each coverage area in the received list of general handoff candidates: determining available downlink resources in the coverage area; and making a determination as to whether or not the available downlink resources in the coverage area are sufficient to meet the downlink-resource demand and if the determination is that the available downlink resources in the coverage area are sufficient, selecting the coverage area as a candidate for the downlink handoff.

8. The method of claim 7 : wherein selecting the one or more candidates for the uplink handoff from the received list of general handoff candidates further comprises, for each coverage area in the received list of general handoff candidates, comparing the available uplink resources in the coverage area to available uplink resources in other coverage areas in the received list of general handoff candidates; and wherein selecting the one or more candidates for the downlink handoff from the received list of general handoff candidates further comprises, for each coverage area in the received list of general handoff candidates, comparing the available downlink resources in the coverage area to available downlink resources in other coverage areas in the received list of general handoff candidates.

9. The method of claim 1 , further comprising: based on movement of the mobile station over a predetermined period of time, determining a mobility factor that quantifies the movement of the mobile station; using the mobility factor as a further basis for selecting the one or more coverage areas in the access network as candidates for an uplink handoff of the uplink connection; and using the mobility factor as a further basis for selecting the one or more coverage areas in the access network as candidates for an downlink handoff of the downlink connection.

10. The method of claim 1 , wherein performance of the method is conditioned upon authorization for premium service.

11. A method for selecting one or more target coverage areas for a bidirectional handoff, the method comprising: (a) an access network providing a connection for a mobile station to engage in a communication, wherein the connection comprises an uplink connection for uplink traffic in the communication session and a downlink connection for downlink traffic in the communication session; (b) the access network receiving a message from the mobile station that identifies one or more candidates for the uplink handoff and one or more candidates for the downlink handoff; (c) the access network determining uplink-resource demand and downlink-resource demand of the mobile station, for the communication session; (d) based, at least in part, on the uplink-resource demand, the access network selecting a first target coverage area to which an uplink handoff of the uplink connection should be directed, wherein the first target coverage area is selected from the one or more candidates for the uplink handoff; and (e) based, at least in part, on the downlink-resource demand, the base station selecting a second target coverage area to which a downlink handoff of the downlink connection should be directed, wherein the second target coverage area is selected from the one or more candidates for the downlink handoff.

12. The method of claim 11 , further comprising: the access network initially broadcasting a message that identifies a plurality of coverage areas as general candidates for a bi-directional handoff; wherein the one or more candidates for the uplink handoff and the one or more candidates for the downlink handoff are selected from the general candidates.

13. The method of claim 11 , further comprising the access network sending a message to the mobile station that identifies the first target coverage area for the uplink handoff and the second target coverage area for the downlink handoff.

14. The method of claim 11 , further comprising the access network conditioning performance of the method on an initial determination that the mobile station or a user of the mobile station is authorized for premium service.

15. A method for selecting candidates for a handoff of a connection between a mobile station and an access network, wherein the connection comprises an uplink connection for uplink communications and a downlink connection for downlink communications, the method comprising: the access network initially broadcasting a message that identifies a plurality of coverage areas as general candidates for a bi-directional handoff; the access network determining an uplink-resource demand and a downlink-resource demand by the mobile station for communications via the connection; based, at least in part, on the uplink-resource demand and the downlink-resource demand, the access network making a determination as to whether to operate in a first mode or a second mode, wherein operation in the first mode comprises using a standard handoff process, and wherein operation in the second mode comprises using a bidirectional handoff process, where the bidirectional handoff process comprises an uplink handoff of the uplink connection and a downlink handoff of the downlink connection; if the determination is to operate in the second mode, then: (i) identifying one or more coverage areas from the general candidates as candidates for the uplink handoff; and (ii) identifying one or more coverage areas from the general candidates as candidates for the downlink handoff; and if the determination is to operate in the first mode, then the access network selecting one or more coverage areas as candidates for a standard handoff performed according to the standard handoff process, wherein the standard handoff process comprises a handoff of both the uplink and downlink connections to a single coverage area.

16. The method of claim 15 , wherein identifying one or more coverage areas as candidates for the uplink handoff of the uplink connection and one or more coverage areas as candidates for the downlink handoff of the downlink connection comprises: sending a preferred-coverage-area prompt message to the mobile station; and receiving a preferred-coverage-area message from the mobile station, wherein the preferred-coverage-area message is received as a response to the preferred-coverage-area prompt message, and wherein the preferred-coverage-area message identifies the one or more candidates for the uplink handoff and the one or more candidates for the downlink handoff.

17. The method of claim 16 , further comprising, if the determination is to operate in the first mode, then selecting an uplink-target coverage area for the uplink handoff and a downlink-target coverage area for the downlink handoff, wherein the first target coverage area is selected from the candidates for the uplink handoff, and wherein the second target coverage area is selected from the candidates for the downlink handoff.